Behavior of bolted lap joints in above ground liquid-filled steel cylindrical tanks

Leakage is the main concern in steel bolted liquid tanks. In this study, the performance of this type of construction is investigated using a detailed finite element (FE) analysis. The validity of AWWA design practice in terms of the safe design of this type of structure at a wide range of service loads is evaluated. The FE analysis is performed in two stages using shell and solid elements in a three-dimensional ANSYS environment including the effect of geometric nonlinearity. The proposed FE model is capable to estimate the ultimate behaviors such as capacity curve, yield/failure pattern, and the occurrence of ovalling and curling. The FE results are compared with experimental ones and a good agreement is found. This study shows that the bolt arrangement selected in design can efficiently improve joint performance. It is recommended to use the limited deformation criterion in the leak-resistant design of bolted lap joints.

One-sided repair of corroded steel girder end with high-strength bolted doubler plate and evaluation of its resiliency after the repair

<p>Repair of steel girder end is sometimes conducted from one side when work space is restricted or corrosion extent is small. This study focuses on repair with high-strength bolted doubler plate as effective and quick one-sided repair method of corroded girder end. FEA was conducted to evaluate the resistance of intact, corroded and repaired girder and to investigate geometrical dimensions of the doubler plate for enhancing its resiliency. From obtained results, both high repair effect and resiliency can be secured with one-sided bolted and small plate, if the web plate and bearing stiffener is prevented from buckling. As contact force between doubler plate and lower flange is the most important to resisting mechanism, they should be touched with each other. Regarding bolt arrangement, it’d be desirable to reduce the distance between lower flange and end bolt. Finally, the repair work such as jack-up and perforation has almost no influence on the ultimate strength.</p>

The Influence of Bolt Layout Form to the Dynamic Stiffness of the Column

In the case of the column materials to determined, the lower natural frequency of column is determined by the number of coupling bolts and bolt arrangement. In this paper, by three-dimensional modeling software of Solidwork column model of hobbing is set up, then by using ANSYS finite element analysis software. The initial four order natural frequency to the different number of connection bolts and the different arrangement of bolt are respectively calculated. After the initial four order natural frequency are contrasted, we conclude that in the case of merely considering dynamic stiffness this study reach it is the most reasonable to select 8-12 bolts in the hobbing of YKQ31300, and different bolt arrangement of effects on the dynamic stiffness of the column is very small and can be ignored.

Optimization Research on the Bolt Arrangement of a Double-Wall Steel Insulation Silo with Multiple Bolted Joint

Double-wall fabricated steel insulation silo with multiple bolted joints is a new structure form of silo. The number of bolt studs used in the1000-ton silo is 12240 which take too much time and money. In order to cut down the cost and shorten the construction period, 6 alternative schemes are put forward to optimize the bolt arrangement. By comparison, Schemes 6 is adopted. The model which uses the original bolt arrangement is defined as Model 1. The optimized model is defined as Model 2. The stress and deformation of these two models were comparatively analyzed. The results show that the maximum stress and the maximum displacement of Model 2 are both smaller than the specified values. Furthermore, the number of bolt studs used in Model 2 is 6600 which is 5640 less than the original number. The bolt studs are saved 46.1%.

Block Shear Behaviours of Stainless Steel Channel Bolted Joints with Four Bolts

The introduction of thin-walled stainless steel in buildings has been increased gradually for ensuring the sustainability thanks to excellent corrosion resistance and durability. Many studies on structural behaviors of stainless steel bolted connection fabricated with plane plate have been carried out. This paper is aimed at investigating the ultimate behaviors such as ultimate strength, fracture mode and out of plane deformation(i.e. curling) of channel bolted connection of cold-formed austenitic stainless steel with four bolts (2×2 bolt arrangement). End distance parallel to the direction of applied force is adopted as main variables. Specimens are planned with block shear fracture in ultimate state. In case of bolted connections with a long end distance, curling has also been observed. Ultimate strengths by test results are compared with those of current ASCE design specification and the influence of curling on ultimate strength is discussed.

An Experimental Study on Structural Behaviours of Single Shear Cold-Formed Stainless Steel Bolted Connections with Two Bolts

The application of stainless steel in buildings has been increased gradually with excellent life cycle cost for ensuring the sustainability in structures for the reduction of green house gas emission. Especially, the purpose of this paper is to investigate the structural behaviors such as ultimate strength, fracture mode and out of plane deformation, i.e., curling of single shear bolted connection of cold-formed austenitic stainless steel with two bolts (2×1 bolt arrangement). Plate thickness and end distance parallel to the direction of applied force are considered as main variables. The curling was also observed in the bolted connections with a long end distance and edge distance as the previous researches. Curling occurrence resulted in the change of fracture modes in connections with same bolt arrangement and end distance and ultimate strength reduction.